Lighting is a fundamental element for allowing a human to gain a sight. Such lighting comprises a wide variety of different light sources, including sunlight, fire, different types of traditional incandescent light, the more energy conservative CFL light, LED light, as well as the more efficient laser light and etc.
Each of the foregoing light sources has its specific application areas. For example, sun light is typically enough for outdoor activities in day time; while it is not very useful in a closed area. These artificial (human made) light sources are usually used indoors. They are able to provide lighting in different situations and at different locations. However, in certain specific areas, including the lighting for a long yet narrow hallway and a smoke filled area, most of the conventional light sources are not able to provide lighting with desirable depth perception and forward visibility. On the other hand, in those specific areas including the long narrow hallway and the smoke filled area, such features including depth perception and forward visibility are even more important and necessary. For example, in a smoke filled area at a fire scene, a good lighting is able to save many lives.
In view of the foregoing, a specific lighting device which is capable of functioning properly in areas like a long narrow hallway or a smoke filled area in urgent needs, in order to provide desirable depth perception and forward visibility.
Up to date, most of the existing technologies or available lighting devices, which are purported to function in the foregoing areas, are not capable of providing satisfactory results. Some devices can only provide poor lighting results in these situations. While other devices are capable of providing relatively better lighting results, yet they typically require complex structure or infrastructures, such as certain wiring work, which are actually what people try to avoid when walking in a long narrow hallway or escaping from a smoke filled fire scene.
As mentioned above, the existing technology may need complex design and/or supporting wiring or other components in order to provide desirable lighting to certain areas such as long narrow hallway, small room and so on. It is common for an infrastructure of wiring and/or fiber optics to be utilized in order to achieve lighting along stepped areas or simply to have a wide reflective base light such as a plug in night light for radial illumination or side wall mounted units. Some laser light fire evacuation systems need complex infrastructures in which beams of laser light are wired into the ceiling using fiber optics and embedded laser diodes controlled by a central unit with possible mechanical apparatus such as a rotating mirror. In some other existing technologies, fiber optics is used as wall mounted units or light strips along the path of a hallway for area illumination.
The above mentioned existing devices are apparently not very efficient and not easy to use. In this respect, the laser lighting device and application thereof in the present invention are able to provide a better lighting, especially in such areas, including a long narrow hallway, a smoke filled room or an underwater environment with certain turbidity. This device departs from the conventional design of the modern day lighting system and provides desirable depth perception and forward visibility. In addition, such narrow area lighting utility is enabled without the need for more complex lighting connection infrastructure.
Laser light has already been used in fire escape system to overcome the less visibility of lights when the smoke becomes thick. Additionally its light beams are serially staged to turn on as to lead for escape. Unfortunately, the laser light is not used to project dots of light refracting (bending) on the surfaces to identify planes radiating along the way to guide an individual toward the exit in providing depth perception and forward visibility. In addition, the currently available laser lighting devices do not function well in a smoke filled room. If the laser light is very bright, then the smoke (tiny particles forming the smoke) or turbidity will reflect a strong light backward, which would present the user to see any details other than a blinding sight field. On the other hand, if the laser light is not that bright, then the smoke (small particles) may absorb a substantially part of the light, which may render the detectable forward distance too short to be useful.
In light of the foregoing, it therefore an objective of the present invention to provide a laser lighting device, which is able to offer a desirable depth perspective and forward vision; and at the same time, avoid the situations that a laser light is reflected by smoke particles thus to form a blinding sight field without discernible details and that a laser light is absorbed by the smoke particles and thus lost in a short distance before traveling enough distance in a smoke.